It's been over a year since I reviewed NVIDIA's flagship GeForce GTX 295 Graphics Processing Unit (GPU). Since that time, NVIDIA has been anxiously waiting to reveal the performance behind their next-generation GPU - code named GF100, which is based on third-generation Streaming Multiprocessor (SM) architecture.

In breaking down the GF100 nomenclature, the "GF" denotes that the chip is a graphics product based on the Fermi architecture, while the "100" indicates that it is the high-end part of the "GF" family of GPUs. The two GPUs being launched today are the high-end GeForce GTX 480 and GeForce GTX 470 at suggested retail prices of $499 and $349 respectively.

NVIDIA overcame numerous obstacles in designing and manufacturing the GF100 GPU, which contains a whopping three billion transistors and is matched with Graphics Double Data Rate version 5 (GDDR5) memory.

Packing three billion transistors on an all-new 40nm fabrication process was a major challenge and a contributing factor in launching a DirectX 11-based GPU approximately six months after AMD released the Radeon 5 Series. NVIDA had planned on launching the GeForce GTX 480 back in October of 2009, when Windows 7 debuted.

The GF100 GPU is a multi-functioning chip capable of processing graphics and physics data streams, simulating artificial intelligence and rendering advanced cinematic effects including ray-tracing and 3D stereo gaming. Other features, courtesy of DirectX 11, are also hardware-accelerated by GF100.

In regards to availability, NVIDIA stated in a recent conference call that the number of units available will be in the "tens of thousands." Widespread e-tail availability of both the GeForce GTX 480 and GeForce GTX 470 should begin to take place during the week of April 12, 2010.

ARCHITECTURE

Microprocessors are complex products and the GF100 is no exception. NVIDIA's GF100 White Paper provides detailed architectural information. The information presented below is a summarization as the following diagram illustrates the layout of the GPU.

Key features hardware-accelerated by GF100 are a result of enhancements to DirectX 11, which is an Applications Programming Interface (API) developed by Microsoft and primarily used in 3D game development.

These features include tessellation, displacement mapping and DirectCompute. One of the strengths of the GF100 design is in its distributed geometry processing architecture.

The GF100 architecture is said to scale with tessellation complexity and can be verified with the updated version of the Unigine Heaven benchmark.

DirectCompute

DirectCompute is part of the DirectX 11 API and used for general purpose computing on GPUs. DirectCompute taps into the parallel computing power of GPUs to develop computing applications in consumer and professional markets. The technology is similar to OpenCL (Open Computing Language) and CUDA.

CSAA has native support of alpha-to-coverage (transparency multisampling) on all samples, which provides smoother rendering of fences, foilage, wires and transparent textures.

Jittered Sampling

Jittered sampling is a new feature that improves the quality of soft shadows. In technical terms, jittered sampling is a stochastic (random) process in which values are sampled uniformly over a rectilinear (formed by straight lines) sub-space. The exact position of the respective sample in each sub-rectangle is thereby varied randomly.

We begin with head-to-head performance against NVIDIA's previous generation of high-end GPUs. NVIDIA’s own benchmarks reveal that DirectX 9 / DirectX 10 performance of the GeForce GTX 480 surpasses the GeForce GTX 285 by a factor of 1.5x to 3.5x. Our results, at the resolutions of 1920x1200 and 2560x1600 with no, 4x and 8x antialiasing, are below.

* Lack of memory likely caused the poor performance of the GeForce GTX 280 and GTX 295 at 2560x160 with 8x AA.

PERFORMANCE vs. RADEON HD 5870

Alien vs. Predator

Dirt 2

Just Cause 2

Neverwinter Nights 2

Sacred 2

S.T.A.L.K.E.R. Call of Pripyat

Unigine Heaven Benchmark v2.0

DiRT 2 Screenshots and Performance

Colin McRae: Dirt 2 is a state-of-the-art racing game that was released in September of 2009. Dirt 2 is powered by the third generation EGO Engine’s award-winning racing game technology and features DirectX 11 technology. Dirt 2 received an overall ranking in the 90 percentile range from review web sites.

The Dirt 2 screenshots are from the GeForce GTX 480 at a resolution of 2560x1600 with 8xQ CSAA.

Dirt 2 was benchmarked on the London track with Ultra graphics settings at the resolution of 2560x1600. Dirt 2 supports antialiasing modes native to the GeForce Series and results for 8x, 8xQ, and 16x Coverage Sampling (CS) antialiasing are provided.

At 4x and 8x multisampling antialiasing, the average frame rate of the GeForce GTX 480 exceeded that of the Radeon HD 5870 by 10% (56 vs. 51 fps) and 14% (56 vs. 49 fps) respectively.

The Radeon HD 5870 puts up a strong performance against the GeForce GTX 480. Codemasters had been using the Radeon 5 Series to develop Dirt 2 well before DX11 class graphics cards became publicly available. With Codemasters getting an early start in DirectX 11, ATI chose to bundle Dirt 2 with selected Radeon 58xx and 57xx graphics cards.

Just Cause 2 Screenshots and Performance

The Just Cause 2 screenshots are from the GeForce GTX 480 and were taken at the resolution of 1920x1200 with 32x CSAA.

Just Cause 2 debuted on March 23, 2010 and was developed jointly by Avalanche Studios and Eidos Interactive. The graphics engine was programmed internally under the name Avalanche Engine 2.0.

In Just Cause 2, the player is free to roam the game's open world and obtain a variety of weapons from black market suppliers. The game received positive reviews from critics with an 83 rating from Metacritic for the PC version.

Just Cause 2 features three in-game benchmarks, which report an average frame rate. The minimum frame rate was furnished by Fraps and the benchmark used was the Desert Sunrise flyby.

Note that the following results are with two advanced graphics settings, exclusive to the GeForce GTX 480 (Bokeh Filter and GPU Water Simulation), enabled.

After examining the initial benchmark results for Just Cause 2, I noticed that the Radeon HD 5870 consistently outperformed the GeForce GTX 480 by a significant margin.

I began to look for reviews of the GeForce GTX 480 that had benchmark results from Just Cause 2. Some of the results added to my confusion, which were mainly due to a lack of review details concerning testing parameters.

I eventually discovered that the inconsistency was caused by two advanced graphics settings exclusive to the GeForce GTX 480 - Bokeh Filter and GPU Water Simulation. Both options were enabled when I originally benchmarked Just Cause 2 and they should have been disabled when comparing performance to the Radeon HD 5870.

Added 05-25

GeForce GTX 480 vs. Radeon HD 5870

The GeForce GTX 480 proves to be the better overall performer in this benchmark. At less-intensive graphics settings, the GeForce GTX 480 offers 20-30% higher average frame rates over the Radeon HD 5870. Minimum frame rates were a draw.

Also note the performance of 32x CSAA, which closely matches the performance of 8x MSAA.

With no antialiasing, both graphics cards offer similar performance in the S.T.A.L.K.E.R. Call of Pripyat benchmark . At 4x AA, the GeForce GTX 480 outperformed the Radeon HD 5870 by an average of 25%.

As expected, the GeForce GTX 480's tessellation engine is powerful when compared to the Radeon HD 5870. Across all tessellation settings, the average frame rate of the GeForce GTX 480 was 42% higher than that of the Radeon HD 5870 and the minimum was a whopping 92% higher.

Added 05-30

Benchmarks from the standalone Alien vs. Predator benchmark along with a couple of titles that I've been playing - Neverwinter Nights 2 and Sacred 2.

Alien vs. Predator Performance

Aliens vs. Predator uses the Asura engine, which was developed in-house by Rebellion. The engine supports DirectX 11 and makes use of the following features - Multisampling Antialiasing, Hardware Tessellation and Advanced Shadows.

Did you know that differences between two images can be quantified and displayed? With The Compressonator, two images can be compared and the differences revealed. The tool has a zoom feature and differences can also be intensified should they become difficult to identify.

Using one of my favorite antialiasing testing tools, FSAA Tester, a screenshot of each of the available antialiasing modes available on the GeForce GTX 480 was captured.

Note that the level of antialiasing was "forced" by selecting "Override any application setting" in the driver control panel.

Antialiasing is a technique that gives edges a smoother-looking appearance. It is accomplished by comparing the color of adjacent pixels to the pixel that is being antialiased. The color of the pixel being antialiased may change as a result of the comparison.

The adjacent pixels that are compared are referred to as samples. The number of samples to use in the comparison, along with the sample pattern, will vary depending on the type and level of antialiasing being used.

These screenshots can be used to conduct your own comparions using The Compressonator:

Even at 40nm, there is no getting around the fact that an air-cooled GF100 GPU will have higher than average idle and load temperatures - even with its heat pipe design. NVIDIA had even been making changes to the heatsink design over the last few weeks leading up to today's launch.

With the default fan speed set at 44% and the side of the computer enclosure open, idle GPU temperature hovered around 46° C. Using Furmark’s stress test, GPU temperature reached 94° C with the fan at 92%. Fan noise became noticeable around the 55% mark.

At these high temperatures the heat-pipes protruding from the side of the graphics card enclosure were scalding hot. Fan noise was also an issue and I was determined to come up with a solution to decrease GPU temperature and fan noise.

Since the side of the enclosure was open, a fix was pretty simple. I attached a 120mm fan to the top of the enclosure with electrical tape and pointed it directly at the exposed heat pipes. With the fan running at 1500RPM, the GPU temperature gradually dropped a total of 11° C. Furthermore, the noise of the 120mm fan began to drown out the fan on the graphics card, which eventually throttled down to 55%.

Data in the table below was collected by GPU-Z with FurMark's stability test running in a window, at the resolution of 1920x1200 and 8x antialiasing, during the test cycle.

Beginning with the area marked in red titled HEATUP CYCLE, GPU fan speed was set to automatic. As the test begins, FurMark keeps the GPU loaded at 99% and temperature increases quickly. At idle, the GPU temperature was 52° C. Within two minutes, the temperature reached 96° C with the fan speed at 85%.

The second and third parts of the test are labeled COOL DOWN CYCLES. In the second test, with the side of the case opened, a 120mm fan, running at 1750 RPM, was positioned directly at the exposed heat-pipes. In one minute, GPU temperature and fan speed dropped to 92° C and 83% respectively. At the 7.8 minute mark, GPU temperature dropped to 86° C with the fan speed at 71%.

The last part of the test consisted of manually setting the fan speed while continuing to use the 120mm fan. At the 11 minute mark, fan speed was increased from 71% to 81% and GPU temperature dropped to 81° C. Fan speed was increased to 91% shortly after the 11 minute mark and the final GPU temperature ended up at 75° C.

GPU TEMPS AND FAN SPEED TESTING

Based on having tested the GeForce GTX 480 for the past two weeks, I would say that a fan speed of 80% is the threshold where the noise level becomes significant. At high GPU temperatures, typically starting at 95° C, fan RPMs ramp up quickly. Once the GPU temperature stabilizes, fan speed tends to remain constant or drop slightly from that point forward.

I put my observation to the test by running a series of benchmarks from a variety of games and applications. In addition to the results below, I provide screenshots that report GPU temperature and fan speed. Results indicate the GPU stabilization temperature and the fan speed that was needed to achieve those results.

In Batman Arkham Asylum, a 57% fan speed was needed to maintain a GPU temperature of 89° C. On the other hand, a fan speed of 78% was necessay to stabilize a GPU temperature of 91° C when running FurMark.

There are a couple of points to take away from this exercise. First, the GeForce GTX 480 GPU runs hot under load with the default fan profile. NVIDIA doesn't beat around the bush, as Drew Henry, General Manager of GeForce products, had this to say on NVIDIA's nTersect blog.

Quote:

We wanted to let you know that we've also heard your concerns about GTX 480 with respect to power and heat. When you build a high performance GPU like the GTX 480 it will consume a lot of power to enable the performance and features I listed above. It was a tradeoff for us, but we wanted it to be fast. The chip is designed to run at high temperature so there is no effect on quality or longevity. We think the tradeoff is right.

The second point, is that no test required a fan speed of 80% to stabilize GPU temperature. As I mentioned previously, fan noise becomes slightly noticeable around the 55% mark. Upping the speed to the 70% or 75% mark certainly increased the noise level, which I can accept when compared to the noise that's produced at 80%.

Keep in mind that testing was done with the side of the enclosure open.

ADVANCED FAN CONTROL SOFTWARE

Having read discussions in the GeForce GTX 400 Series Forum on advanced fan control software, I definitely had to check out MSI's Afterburner. This handy utility allows custom fan profiles to be created. The interface is slick and consists of defining the fan speed (by percentage) based on GPU temperature.

For example, the following readings are from running the Furmark stress test for 120 seconds with the default fan profile of the GeForce GTX 480. The topmost graph reports GPU temperature, the middle graph reports GPU usage and the graph on the bottom reports on the fan speed.

GPU usage increased to 99% upon launching FurMark. After 120 seconds, GPU temperature reached 95° C. Looking at the fan speed graph, we see that it remained at the default setting of 44% for almost 60 seconds and ramped up to 87% at the end of the test.

This exercise was interesting as I spent over an hour testing with Furmark before completing my custom fan control profile, which looks like so.

MSI's Afterburner is a handy utility for owners of the GeForce GTX 480.

FINAL RATING

At nV News, we award products with a base hit, home run or grand slam. The GeForce GTX 480 came very close to receiving a home run, but after much thought, I gave it our base hit award. In this case, the base hit would have been a triple instead of a single or double.

The GeForce GTX 480 distinguishes itself with its tessellation performance, but fails to deliver the performance knock-out punch against the Radeon HD 5870. The GeForce GTX 480 also distinguishes itself with its high power requirements and GPU temperatures. This is an area where the Radeon HD 5870 stands out.

UPDATES

03-27
Added screenshots and benchmark results for Dirt 2 on the GeForce GTX 480. Codemasters did a great job by including an easy to use in-game benchmark.

03-28
Posted benchmark results from the GeForce GTX 480 and version 2.0 of the Unigine Heaven benchmark. Results at the resolutions of 1680x1050, 1920x1200 and 2560x1600 across all levels of tessellation are provided. The two remaining titles to be testing on the GeForce GTX 480 are Metro 2033 and Just Cause 2. Just Cause 2 has three in-game flyby benchmarks available. I will need to spend time developing a repeatable, or near as repeatable, gameplay walkthrough to measure performance in Metro 2033.

03-31
Added screenshots and benchmark results for Just Cause 2 on the GeForce GTX 480.

04-01
Included a photograph of the GeForce GTX 480 installed in my system.

04-02
Added a GPU temperature and fan speed testing section near the end of the post. The goal of this exercise was to determine GPU stabilization temperatures and the fan speed needed to achieve those temperatures.

04-04
Added an additional cooling with 120mm fan section near the end of the post. The goal of this exercise was to record GPU temperatures under load while cooling the heat-pipes with a 120mm fan. Added a section that reports on antialiasing image quality. Visual comparisons are provided that report on differences between different levels of antialiasing. This information is located right before the section on GPU cooling.

04-16
Not much to report this past week. Scott Wasson, over at The Tech Report, has commented on the GeForce GTX 480 fan noise in a blog post.

04-18
Installed the Asus Radeon HD 5870 and Catalyst 10.3 drivers, which included a free trial of Lord of The Rings online.

05-02
Added information about the Radeon HD 5870 and compared performance to the GeForce GTX 480 in the DirectX 11 Unigine Heaven benchmark. Across all test results, the average frame rate of the GeForce GTX 480 was 42% faster than the Radeon HD 5870 and the minimum was a whopping 92% faster. Also included a blurb on idle and load GPU temps of the Radeon HD 5870.